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Valkster
07-31-2025, 06:35 PM
Hello, all. I have a lot of information printed off from the forum on paint and body for my project. Some of it is really old information, while some of it is newer. Here is what I plan to do based upon what I have found from you guys that do a lot of these cars, and from paint/body channels on YouTube. Please see if I am on the right track moving forward. I have done paint and body before, twice properly, and twice as a kid that didn't know anything (and it showed). My last experiences have been years ago and neither of those cars were fiberglass.

1. Once the gapping, fitting, and filling are done I will take the body off the chassis for the remainder of the paint/body process. I know there are many that paint it on the chassis, but I am lazy and taking the body off take minutes while masking the chassis would take hours...plus I am afraid I will not get into hard-to-reach areas with primer/paint.

2. After three coats of polyester high-build primer (I'm using UPOL) I will block it with 150 dry. My main question or concern here is that 150 grit is still pretty course, still shaping the body more than prepping for paint from various sources I have read/watched. With the doors, hood, and truck lid separate from the body, do I need to take any special precautions to prevent messing up all the gapping/filling/blending between panels that I have done? I speak mainly about nearing the edges of the various panels where they mate with the body and the body where it nears the panel openings.

3. Apply 3 coats of urethan 2K primer (I'm using UPOL 2K catalyzed here) and block dry with 320 and finish with 600 wet or dry.

4. Also, in regard to the high build primer and the 2K primer, do most/all of you put three full coats of high-build and 2K on the insides of panels too, or do most of you use less in those areas because they are less seen and seem less prepped based upon forum posts?

5. Apply one coat of sealer, paint stripes, mask stripes, paint body, and finally clear coat (then all post-paint work as needed)

Any guidance or current opinions or changes to normal procedure would be appreciated.
Thanks,
Mark

Jeff Kleiner
07-31-2025, 07:36 PM
You've got it. When blocking the polyester with 150 you're only making it flat and smooth with no texture left, not actually shaping the panels. Same with the 320 and 600 on the urethane. Inside and outside of the hood, trunk and doors all get treated the same as the outside; 3 coats of everything (except sealer)

Valkster
07-31-2025, 07:58 PM
Ok, thanks Jeff...I see where you guys spend a LOT of hours on the body to get them looking beautiful! My passenger door looks good now that I have put the long straight edge and measuring tape away, lol. It was a learning process; I thought the door was spot on with its location. Then, after sanding a pile of filler off the door/fender I could see 1/32" here and there to tweak on the door position to make the transition look right with the fender. I did use a shorter straight edge as a reference, along with feel. The rounded transition from the door to the cowl took a few tries for me, too, but it looks really nice and continuous now. I have a few minor tweaks to the trunk lid and then tackle the driver's side door before heading to primer!

I appreciate the help,
Mark